FIELD: chemistry.SUBSTANCE: invention relates to an improved method of producing at least one product from acrolein and acrylic acid via partial oxidation of propylene, where a) purified propane is converted at the first reaction step in the presence and/or absence of molecular oxygen, at least one dehydrogenation from a group comprising homogeneous dehydrogenation, heterogeneous catalytic dehydrogenation, homogeneous oxydehydrogenation and heterogeneous catalytic oxydehydrogenation, wherein a gaseous mixture 1 is obtained, which contains unconverted propane and the formed propylene, and b) optional separation from the total amount or partial amount of the gaseous mixture 1 of a partial amount of components other than propane and propylene contained therein, e.g., hydrogen, carbon monoxide, water vapour and/or optional conversion thereof to other compounds, e.g., water and carbon dioxide, and where a gaseous mixture 1' is obtained, which contains propane and propylene, and on at least one of the following reaction steps, c) the gaseous mixture 1 or gaseous mixture 1' or a mixture from the formed gaseous mixture 1' and the remaining gaseous mixture 1 as a component of a gaseous mixture 2 are subjected to heterogeneous catalytic gas-phase partial oxidation of propylene contained in gaseous mixture 1 and/or gaseous mixture 1', wherein a gaseous mixture 3 is obtained, which contains at least one product, d) on at least one separation step, the product is separated from gaseous mixture 3 and from the remaining residual gas, at least propane is returned to the first reaction step, where purified propane is obtained from crude propane which contains ≥90 wt % propane, ≤99 wt % propane and propylene, ≥100 ppm hydrocarbons, having 2 carbon atoms, and ≥100 ppm hydrocarbons, having 4 carbon atoms, under the condition that crude propane is fed into the fractionation column and purified propane is obtained higher than the feeding point under the condition that content of hydrocarbons having 2 carbon atoms, in wt %, in terms of the contained propane, in the purified propane is more than 100% of the corresponding content in crude propane and content of hydrocarbons having 4 carbon atoms, in wt %, in terms of content of propane, in the purified propane is at most 50% of the corresponding content in crude propane.EFFECT: method enables to cut design expenses owing to no separation of C2-hydrocarbons during distillation.48 cl, 1 ex

FIELD: chemistry.SUBSTANCE: invention relates to an improved method for heterogeneous catalytic gas-phase partial oxidation of at least one initial organic compound selected from propylene, isobutene, acrolein, methacrolein, propane or isobutane with molecular oxygen on a fixed catalyst bed freshly put into a reaction space, in which, for partial oxidation, a reaction gaseous mixture containing at least one initial organic compound and molecular oxygen is passed through the fixed catalyst bed, and reaction heat is removed via indirect heat exchange with a liquid heat carrier directed outside the reaction space, and as the quality of the fixed catalyst bed falls with operation time, not all, but part of the fixed catalyst bed is replaced with part of a replacement fixed catalyst bed in order to restore the quality of the fixed catalyst bed, where the specific volume activity of the replacement part of the fixed catalyst bed is lower than that of the replaced part of the fixed catalyst bed in its fresh state.EFFECT: deterioration of the quality of the fixed catalyst bed with operation time is compensated for by replacing part of the fixed catalyst bed with a replacement part of the fixed catalyst bed, where the rate of deactivation of the catalyst is lowest in the disclosed method.10 cl, 2 ex

FIELD: chemistry.SUBSTANCE: according to the method: A) at least two initial gas streams containing propane, which form the reaction gas A, are fed into a reaction zone A, where one of said gas streams contains fresh propane; the reaction gas A is passed through at least one catalyst layer in reaction zone A in which partial heterogeneously catalysed dehydrogenation of propane results in formation of molecular hydrogen and propylene; molecular oxygen is fed into reaction zone A and oxidises molecular hydrogen in the reaction gas A to water vapour, and a gaseous product A is collected from reaction zone A, said product containing molecular hydrogen, water vapour, propylene and propane; B) the gaseous product A collected from the reaction zone A, while feeding molecular oxygen, is used in reaction zone B to supply at least one oxidation reactor with reaction gas B which contains molecular hydrogen, water vapour, propane, propylene and molecular oxygen, and propylene contained in reaction gas B undergoes two-step heterogeneously catalysed partial gas-phase oxidation in reaction zone B to obtain a gaseous product B containing acrylic acid as the end product, unconverted propane, molecular hydrogen, water vapour and carbon dioxide as by-products, as well as other secondary components with boiling point lower or higher the boiling point of water; C) gaseous product B is output from the reaction zone B and acrylic acid, water and secondary components with boiling point higher than that of water contained therein are separated in a first separation zone I through fractional condensation or absorption, wherein the residual gas I contains unconverted propane, carbon dioxide, molecular hydrogen, secondary components with boiling point lower than that of water, as well as, if necessary, propylene and molecular oxygen not converted in reaction zone B; D) residual gas I undergoes further treatment by washing carbon dioxide contained therein, separation of a partial amount of residual gas I, as well as, if necessary, separation of molecular hydrogen contained in the residual gas I using a separating membrane; E) after further treatment, unconverted propane-containing residual gas I is returned to reaction zone A as at least one of at least two propane-containing initial streams, where in reaction zone A, a certain amount (M) of molecular hydrogen is oxidised to water vapour, which makes up at least 35 mol % but not more than 65 mol % of the total amount of molecular hydrogen produced in reaction zone A and, if necessary, fed into said reaction zone A.EFFECT: improved method of producing acrylic acid from propane.22 cl, 1 ex

FIELD: chemistry.SUBSTANCE: invention relates to novel compounds of general formula (I), in which X denotes a CHO, CH2OH or CH2OC(O)R group, where R denotes a straight of branched C1-C5 alkyl chain; as well as to a synthesis method, particularly synthesis of 6,8-dimethylnon-7-enal (1) through hydroformylation of 5,7-dimethylocta-1,6-diene. The invention also relates to fragrant compositions containing formula (I) compounds. Owing to their fragrant properties, these compounds are of great interest in perfumery, particularly cosmetic products and household chemicals.EFFECT: obtaining novel fragrant compositions.12 cl, 7 ex

FIELD: chemistry.SUBSTANCE: invention relates to improved method of obtaining (meth)acrylic acid or (meth)acrolein, which includes process of catalytic gas-phase oxidation for obtaining (met)acrylic acid or (meth)acrolein by supplying propylene, propane or isobutylene and gas, containing molecular oxygen, into reactor, filled with catalyst, which contains composition of metal oxides, including Mo, where gas, containing molecular oxygen, is continuously supplied from outside on catalyst both during installation operation, and during stoppage of catalytic gas-phase oxidation process.EFFECT: obtaining gaseous reaction product, which includes (meth)acrylic acid or (meth)acrolein, in which reduction of catalyst activity and selectivity of target product formation do not occur when installation operation is restarted after stoppage of catalytic gas-phase oxidation process.2 cl, 2 tbl, 2 ex